Thermodynamics of the evolving Lorentzian wormhole at the apparent horizon is investigated in f(R) gravity. Redefining the energy density and the pressure, the continuity equation is satisfied and the field equations in f(R) gravity reduces to the ones in general relativity. However, the energy-momentum tensor includes all the corrections from f(R) gravity. Therefore, one can apply the standard entropy-area relation within $f(R)$ gravity. It is shown that there may be an equivalency between the field equations and the first law of thermodynamics. It seems that an equilibrium thermodynamics may be held on the apparent horizon. The validity of the generalized second law of thermodynamics (GSL) is also investigated in the wormholes.
